Safe Handling and Recovery of Refrigerants Flashcards

Under the ASHRAE Standard 34 safety classification, what does the designation 'A1' indicate?

Answer: Lower toxicity, no flame propagation

The letter A indicates lower toxicity and the number 1 indicates no flame propagation.

ASHRAE Standard 15 requires what safety device in mechanical equipment rooms containing refrigerants such as R-123 or R-134a?

Answer: A refrigerant sensor/oxygen-deprivation alarm that activates ventilation

ASHRAE 15 requires refrigerant detectors that sound an alarm and start mechanical ventilation when concentrations exceed safe limits.

Which recovery technique is generally fastest for removing a large refrigerant charge?

Answer: Recovering liquid first, such as by the push-pull method

Liquid refrigerant is much denser than vapor, so recovering liquid first (often by push-pull) removes the charge much faster.

How can a technician speed up recovery by manipulating the recovery cylinder?

Answer: Chill the recovery cylinder to lower its pressure

Cooling the recovery cylinder lowers its pressure, increasing the pressure difference that drives refrigerant into it.

Why should hoses used during recovery be equipped with low-loss fittings?

Answer: To minimize refrigerant release when hoses are connected and disconnected

Low-loss fittings close automatically or manually when hoses are disconnected, preventing refrigerant release.

What should a technician do with the oil removed from a refrigeration system or recovery machine after recovery?

Answer: Dispose of it according to federal, state, and local regulations

Refrigerant oil may contain dissolved refrigerant and contaminants and must be handled under applicable waste regulations.

Recovery and recycling equipment manufactured after November 15, 1993 must meet which requirement?

Answer: It must be certified by an EPA-approved testing organization

Recovery equipment made after November 15, 1993 must be certified by an EPA-approved testing laboratory such as AHRI or UL.